Abdus Salam International Center for Theoretical Physics (ICTP), Trieste (2005)

California Institute of Technology: Caltech (1995, 2005)

Cambridge University (1997, 2002)

Cornell University (2005)

Duke University (1997, 2003)

Eindhoven University of Technology (1998, 2001, 2003, 2005)

European Space Agency (ESA), ESTEC, Noordwijk (2006)

GIK Institute of Science & Technology-Topi (1994)

Imperial College of Science, Technology & Medicine (1997, 2002)

LUMS: Lahore University of Management & Science (1994, 2003)

McGill University (2003)

MIT Lincoln Laboratory (1996)

MIT: Massachusetts Institute of Technology (1997)

NASA/Caltech Jet Propulsion Laboratory

Northwestern University (1999)

Old Dominion University (2002)

Oxford University (2005)

Quaid-e-Azam University, Islamabad (1993, 1995)

Rennselaer Polytechnic Institute (1991)

Stanford University (2003)

Swiss Federal Institute of Technology-ETH-Zurich (2004)

Technical University of Delft (2000)

UCLA: University of California Los Angeles (2005)

University College London (1997)

University of California-Santa Cruz (2000)

Univ. of Iowa Medical School (2002)

Univ. of Neuchatel (2003)

University of New Mexico (2004)

University of Pennslyvania (1997, 1998)

University of Southern California (2005)

Yale University (1994)